(a) Field of the Invention
The present invention relates to a jack with a rotary handle sleeve. wherein the handle sleeve of the jack is locked to a rotary supporting seat, or a steel ball bearing or a thrust bearing is installed so that the handle sleeve can rotate leftwards or rightwards. The respective positions of the handle sleeve and the rotary supporting seat have designs for confining the lowest position.
(b) Description of the Prior Art
The prior art jack has a handle tube receiving a handle sleeve. Thereby, the tube can be moved up and down and the piston in the pump is driven to oil. However, the handle tube is confined so that it can only be moved up and down, but cannot be moved left and right. Generally, the four corners of the jack base are mounted with wheels for moving forwards and backwards, but the handle tube cannot rotate leftwards and rightwards. In the space below a car or in a narrow space, if it is desired to adjust the operation direction of the handle tube, movement of the handle tube is confined by the space so that the operation is very difficult. It is often that the top disk of the jack must be aligned to the supported portion of a heavy object, and then is moved to a correct position. This operation can be inconvenient with the prior art devices.
For example, U.S. Pat. No. 6,086,047 discloses a jack with a rotary handle tube, but the hydraulic cylinder and pump of that invention are installed on the upper end of the rotary supporting seat, and the central tube thereof moves upwards vertically. Therefore, the travelling path is very short. Besides, the distance between the rear wheels is too small. Thus, in using, it is possible that the jack is unstable and possibly become tilt.
Accordingly, the primary object of the present invention is to provide a jack with a rotary handle sleeve, wherein a handle sleeve of a jack is locked to a rotary supporting seat. The rotary supporting seat passes through the pump and washers to be locked to the base of the jack. Thereby, handle sleeve may rotate rightwards and leftwards.
Another object of the present invention is to provide a jack with a rotary handle sleeve, wherein the oil return valve is connected to a flexible shaft for controlling the opening and closing of the oil return valve. The handle sleeve and the rotary supporting seat have a design for confining the lower limit.
Another object of the present invention is to provide a jack with a rotary handle sleeve, wherein in the rotary supporting seat, a connected stopping piece is installed between the two supporting plates. Thereby, the handle sleeve is locked behind the rotary supporting seat. Therefore, by the connected stopping piece, the handle sleeve may have a stopping effect in the vertical direction so that the handle sleeve is preferably positioned in the vertically direction. Thereby, the movable roller is in contact with the piston without separating from one another.
Another object of the present invention is to provide a jack with a rotary handle sleeve, wherein predetermined positions of the handle sleeve and rotary supporting seat are installed with an extending stopper and a step-like stopping surface; after the handle sleeve presses downwards, the stopper resists against the stopping surface of the rotary supporting seat so as to be formed with a lower limit. As a result, the piston 21 of the pump is protected from damage due to an overlarge force.
A further object of the present invention is to provide a jack with a rotary handle sleeve, wherein a steel ball bearing or a thrust bearing can be installed between the rotary supporting seat or the base of the jack so that the rotation of the handle sleeve may rotate freely. Thereby, the movable roller is in contact with the piston without separating from one another.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing.